.TH "C:/Users/Matt/Documents/School/Robotics/zebulon/v2/vision/ext/SIFT/sift.h" 3 "13 Oct 2009" "Version 2" "zebulon" \" -*- nroff -*-
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.SH NAME
C:/Users/Matt/Documents/School/Robotics/zebulon/v2/vision/ext/SIFT/sift.h \- 
.SH SYNOPSIS
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.PP
\fC#include 'cxcore.h'\fP
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.SS "Classes"

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.RI "struct \fBdetection_data\fP"
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.SS "Defines"

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.RI "#define \fBSIFT_INTVLS\fP   3"
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.RI "#define \fBSIFT_SIGMA\fP   1.6"
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.RI "#define \fBSIFT_CONTR_THR\fP   0.04"
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.RI "#define \fBSIFT_CURV_THR\fP   10"
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.RI "#define \fBSIFT_IMG_DBL\fP   1"
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.RI "#define \fBSIFT_DESCR_WIDTH\fP   4"
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.RI "#define \fBSIFT_DESCR_HIST_BINS\fP   8"
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.RI "#define \fBSIFT_INIT_SIGMA\fP   0.5"
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.RI "#define \fBSIFT_IMG_BORDER\fP   5"
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.RI "#define \fBSIFT_MAX_INTERP_STEPS\fP   5"
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.RI "#define \fBSIFT_ORI_HIST_BINS\fP   36"
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.RI "#define \fBSIFT_ORI_SIG_FCTR\fP   1.5"
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.RI "#define \fBSIFT_ORI_RADIUS\fP   3.0 * SIFT_ORI_SIG_FCTR"
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.RI "#define \fBSIFT_ORI_SMOOTH_PASSES\fP   2"
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.RI "#define \fBSIFT_ORI_PEAK_RATIO\fP   0.8"
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.RI "#define \fBSIFT_DESCR_SCL_FCTR\fP   3.0"
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.RI "#define \fBSIFT_DESCR_MAG_THR\fP   0.2"
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.RI "#define \fBSIFT_INT_DESCR_FCTR\fP   512.0"
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.RI "#define \fBfeat_detection_data\fP(f)   ( (struct \fBdetection_data\fP*)(f->feature_data) )"
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.SS "Functions"

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.RI "int \fBsift_features\fP (IplImage *img, struct \fBfeature\fP **feat)"
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.RI "int \fB_sift_features\fP (IplImage *img, struct \fBfeature\fP **feat, int intvls, double sigma, double contr_thr, int curv_thr, int img_dbl, int descr_width, int descr_hist_bins)"
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.SH "Detailed Description"
.PP 
Functions for detecting SIFT image features.
.PP
For more information, refer to:
.PP
Lowe, D. Distinctive image features from scale-invariant keypoints. \fIInternational Journal of Computer Vision, 60\fP, 2 (2004), pp.91--110.
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Copyright (C) 2006 Rob Hess <hess@eecs.oregonstate.edu> Note: The SIFT algorithm is patented in the United States and cannot be used in commercial products without a license from the University of British Columbia. For more information, refer to the file LICENSE.ubc that accompanied this distribution.
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\fBVersion:\fP
.RS 4
1.1.1-20070913 
.RE
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.SH "Define Documentation"
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.SS "#define SIFT_CONTR_THR   0.04"default threshold on keypoint contrast |D(x)| 
.SS "#define SIFT_CURV_THR   10"default threshold on keypoint ratio of principle curvatures 
.SS "#define SIFT_DESCR_HIST_BINS   8"default number of bins per histogram in descriptor array 
.SS "#define SIFT_DESCR_WIDTH   4"default width of descriptor histogram array 
.SS "#define SIFT_IMG_DBL   1"double image size before pyramid construction? 
.SS "#define SIFT_INTVLS   3"default number of sampled intervals per octave 
.SS "#define SIFT_SIGMA   1.6"default sigma for initial gaussian smoothing 
.SH "Function Documentation"
.PP 
.SS "int _sift_features (IplImage * img, struct \fBfeature\fP ** feat, int intvls, double sigma, double contr_thr, int curv_thr, int img_dbl, int descr_width, int descr_hist_bins)"Finda SIFT features in an image using user-specified parameter values. All detected features are stored in the array pointed to by \fIfeat\fP.
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\fBParameters:\fP
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\fIimg\fP the image in which to detect features 
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\fIfeat\fP a pointer to an array in which to store detected features 
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\fIintvls\fP the number of intervals sampled per octave of scale space 
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\fIsigma\fP the amount of Gaussian smoothing applied to each image level before building the scale space representation for an octave 
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\fIcontr_thr\fP a threshold on the value of the scale space function $\left|D(\hat{x})\right|$, where $\hat{x}$ is a vector specifying \fBfeature\fP location and scale, used to reject unstable features; assumes pixel values in the range [0, 1] 
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\fIcurv_thr\fP threshold on a feature's ratio of principle curvatures used to reject features that are too edge-like 
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\fIimg_dbl\fP should be 1 if image doubling prior to scale space construction is desired or 0 if not 
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\fIdescr_width\fP the width, $n$, of the $n \times n$ array of orientation histograms used to compute a feature's descriptor 
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\fIdescr_hist_bins\fP the number of orientations in each of the histograms in the array used to compute a feature's descriptor
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\fBReturns:\fP
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Returns the number of keypoints stored in \fIfeat\fP or -1 on failure 
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\fBSee also:\fP
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\fBsift_features()\fP
.RE
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Finds SIFT features in an image using user-specified parameter values. All detected features are stored in the array pointed to by \fIfeat\fP.
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\fBParameters:\fP
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\fIimg\fP the image in which to detect features 
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\fIfea\fP a pointer to an array in which to store detected features 
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\fIintvls\fP the number of intervals sampled per octave of scale space 
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\fIsigma\fP the amount of Gaussian smoothing applied to each image level before building the scale space representation for an octave 
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\fIcont_thr\fP a threshold on the value of the scale space function $\left|D(\hat{x})\right|$, where $\hat{x}$ is a vector specifying \fBfeature\fP location and scale, used to reject unstable features; assumes pixel values in the range [0, 1] 
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\fIcurv_thr\fP threshold on a feature's ratio of principle curvatures used to reject features that are too edge-like 
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\fIimg_dbl\fP should be 1 if image doubling prior to scale space construction is desired or 0 if not 
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\fIdescr_width\fP the width, $n$, of the $n \times n$ array of orientation histograms used to compute a feature's descriptor 
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\fIdescr_hist_bins\fP the number of orientations in each of the histograms in the array used to compute a feature's descriptor
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\fBReturns:\fP
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Returns the number of keypoints stored in \fIfeat\fP or -1 on failure 
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\fBSee also:\fP
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sift_keypoints() 
.RE
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.SS "int sift_features (IplImage * img, struct \fBfeature\fP ** feat)"Finds SIFT features in an image using default parameter values. All detected features are stored in the array pointed to by \fIfeat\fP.
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\fBParameters:\fP
.RS 4
\fIimg\fP the image in which to detect features 
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\fIfeat\fP a pointer to an array in which to store detected features
.RE
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\fBReturns:\fP
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Returns the number of features stored in \fIfeat\fP or -1 on failure 
.RE
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\fBSee also:\fP
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\fB_sift_features()\fP 
.RE
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.SH "Author"
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Generated automatically by Doxygen for zebulon from the source code.
